Page : 1 of 51
KLM Technology
Group
Rev: 03
Practical Engineering
Guidelines for Processing
Plant Solutions
Rev 01 Feb 2007
Rev 02 Feb 2009
Rev 03 May 2012
Co Authors
KLM Technology Group
#03-12 Block Aronia,
Jalan Sri Perkasa 2
Taman Tampoi Utama
81200 Johor Bahru.
Pump Selection and Sizing
Rev 01 - A L Ling
Rev 02 – Viska Mulyandasari
Rev 03 – K Kolmetz
(ENGINEERING DESIGN GUIDELINE)
Karl Kolmetz
KLM Technology Group is providing the introduction to this guideline for free
on the internet. Please go to our website to order the complete document.
www.klmtechgroup.com
TABLE OF CONTENT
INTRODUCTION
Scope
5
General Design Consideration
Type of Pump
6
Process Requirements Parameters
9
DEFINITIONS
11
NOMENCLATURE
13
THEORY
A) Working Principle of Pump
I) Centrifugal Pump
15
15
Centrifugal Pump Impeller & Shaft (Rotating Component)
16
Working Theory-Conversion of Kinetic Energy to Pressure Energy
17
Page 2 of 51
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
II) Positive Displacement Pump
B) Pump Selection
Industry Codes and Standards for Pump Selection & Design
Rev: 03
May 2012
17
18
23
C) Cavitation
24
D) Total Head
25
E) Net Positive Suction Head – NPSH
26
F) Pump Power and Efficiency
28
I) Power
28
II) Hydraulic Power
29
III) Brake Power
29
IV) Pump Efficiency
30
G) Pump Sizing- Step by Step Calculation
TROUBLESHOOTING OF THE PUMP PROBLEMS
31
33
I) Seal Leakage
33
II) Loss of flow
33
III) Loss of Suction
34
IV) Low Discharge Pressure
34
V) Excessive Noise and Vibration
34
VI) Excessive Power Consumption
34
VII) Rapid Pump Wear
35
MATERIAL OF CONSTRUCTION
40
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
Page 3 of 51
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
APPLICATION
Example Case 1: Pump Sizing for water flow
42
Example Case 2: Pump Sizing for Hydrocarbon flow
46
REFEREENCES
50
LIST OF TABLE
Table 1: General selection method for centrifugal pumps
Table 2: General selection method for positive displacement pumps
Table 3: General Centrifugal Pump Problem and Solution
Table 4: Pump Material of Construction for specific services
19
21
35
41
LIST OF FIGURE
Figure 1: Foot mounted overhung pump
Figure 2: Centerline mounted overhung pump
Figure 3: Radically split multistage-single & double casing
Figure 4: Simple Centrifugal Pump
Figure 5: Seven-stage centrifugal pump
Figure 6: Positive-displacement gear-type rotary pump
Figure 7: Selection guides for various type of pumps
Figure 8: Centrifugal Pump Efficiency
7
8
8
15
16
18
29
30
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
Page 4 of 51
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
KLM Technology Group is providing the introduction to this guideline for free
on the internet. Please go to our website to order the complete document.
www.klmtechgroup.com
INTRODUCTION
Scope
This design guideline assists engineers and operations personnel to understand the
selection and sizing of pumps. A pump is one of the most important pieces of
mechanical equipment that is present in industrial processes. A pump moves liquid
from one area to another by increasing the pressure of the liquid above the amount
needed to overcome the combined effects of friction, gravity and system operating
pressures.
There are two types of pump which are generally used in industrial processes: positive
displacement pump and centrifugal. It is important to choose the suitable type of
pump based on process requirement and fluid process properties. The functions and
types of pump are explained in detail under the General Design Guideline section.
The theory section covers the selection method of the pump based on their application
and engineering calculations for the sizing of the pump. When sizing the pump, the
understanding of concept of cavitation is very important. Cavitation is an abnormal
condition that can result in loss of production, equipment damage and worst of all,
personnel injury. To prevent pumps from having this problem, the correct design
should be followed by applied the correct theory when carrying out the activities of
pump sizing and selection.
In the application section of this guideline, four case studies are shown and discussed
in detail, highlighting the way to apply the theory for the calculation. Generally used
theory, such as Bernoulli’s theory, is used as the basic of calculation because it is
applicable for various conditions. This theory is applied in calculation of the NPSH of
the pumps, which is shown in detail in this section. The case studies will help the
engineer do the selection and sizing for the pumps base on their own plant system.
Example Calculation Spreadsheets is attached in the end of this guideline. This
Example Calculation Spreadsheets is made based on case studies in the application
section to make the reader easier to learn.
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
Page 5 of 51
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
INTRODUCTION
General Design Consideration
Type of Pump
The selection of type and construction of a pump is very important to meet the process
specification and proper application. Knowledge of the variety of pumps in the market
should be review. It is mentioned before, that there are two general types of pump in
today’s industry: positive displacement and centrifugal (dynamic) pumps.
Positive Displacement Pumps
Positive displacement (PD) pumps work by allowing a fluid to flow into some enclosed
cavity from a low-pressure source, trapping the fluid, and then forcing it out into a
high-pressure receiver by decreasing the volume of the cavity. Some examples of PD
pumps are: fuel and oil pump in most automobiles, the pumps on most hydraulic
systems, and the heart of most animals.
Some general types of the positive displacement pumps are as below:
a) Reciprocating Pump
Reciprocating pumps create and displace a volume of liquid, their
“displacement volumes”, by action of a reciprocating element. Liquid
discharge pressure is limited only by strength of structural parts. A pressure
relief valve and a discharge check valve are normally required for
reciprocating pumps
Reciprocating pumps can be further classified into three types of pump as
below,
i) Piston Pumps
ii) Packed Plunger Pumps
iii) Diaphragm Pumps
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
Page 6 of 51
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
b) Rotary Pump
Rotary pumps function with close clearances such that a fixed volume of
liquid is displaced with each revolution of the internal element. Rotary pumps
include:
i)
ii)
iii)
iv)
Gear Pump
Lobe Pump
Vane Pump
Screw Pump
All those pumps above have the similar working principles: pumping the liquid
with the help of rotating elements. The difference lies on the rotating
elements; they could be gear, lobe, vane, or screw.
Centrifugal Pumps
Centrifugal pumps are dynamic pumps. A centrifugal pump raises the pressure of the
liquid by giving it a high kinetic energy and then converts it into pressure energy
before the fluid exits the pump. It normally consists of an impeller (a wheel with
blades), and some form of housing with a central inlet and a peripheral outlet. The
impeller is mounted on a rotating shaft and enclosed in a stationary casing. Casings
are generally of two types: volute and circular. The impeller design and the shape of
the casing determine how liquid is accelerated though the pump.
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
Page 7 of 51
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
SECTION :
Rev: 03
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
May 2012
Some general types of the centrifugal pumps are as below:
a) Overhung pump
A pump with the impeller(s) cantilevered from its bearing assemblies is
classified as an overhung pump.
Figure 1: Foot mounted
overhung pump
Figure 2: Centerline
mounted overhung pump
b) Between bearings pump
A pump with the impeller(s) located between the bearings is classified as a
between bearings pump. The pump may be single-stage (one impeller), twostage, or multistage. It can be axially (horizontally) split or radially split.
Figure 3: Radically split multistage-single & double casing.
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
Page 8 of 51
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
c) Vertically suspended pump
A pump with the impeller(s) cantilevered vertically and the suction nozzle
typically submerged is classified as a vertically suspended pump.
c) Seal-less pump
Seal-less pumps are special pumps which do not require shaft seals.
Construction for seal-less pumps is driven by canned motors or magnetic
couplings. It is normally used in process involve extremely hazardous fluid,
where leakage cannot be tolerated.
d) Submersible pump
Submersible pumps are designed to prevent pump cavitation .The driver
components inside are completely surrounded by the pumped fluid.
e) Horizontal self-priming pump
Horizontal self-priming pumps are designed to create a vacuum at the pump
inlet. This enables the pump to “suck” fluid into its casing. The suction nozzle
of the pump can therefore be located above the level of liquid being pumped.
Centrifugal pumps are used in more industrial applications than any other kind of
pump. This is primarily because these pumps offer low initial and upkeep costs.
Traditionally these pumps have been limited to low-pressure-head applications, but
modern pump designs have overcome this problem unless very high pressures are
required.(4) The single-stage, horizontal, overhung, centrifugal pump is by far the most
commonly type used in the chemical process industry. (3)
Basically, pump selection is made on the flow rate and head requirement and with
other process considerations, such as material of the construction pumps for the
corrosive chemical service or for the fluid with presence solids in the stream.
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
Page 9 of 51
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
Process Requirements Parameters
In designing the pump, the knowledge of the effect of parameters; such as pump
capacity, NPSH, pumping maximum temperature, specific gravity, fluid viscosity, fluid
solid content, and the other process requirements are very important. All of these
parameters will affect the selection and design of the pump which will affect the
performance of the pump in the process.
Pump capacity is a parameter plays an important role when selecting the pump.
Capacity means the flow rate with which liquid is moved or pushed by the pump to the
desired point in the process. It is commonly measured in either gallons per minute
(gal/min) or cubic meters per hour (m3/hr). The capacity usually changes with the
changes in operation of the process. A minimum required flow rate need to be
specified, this is important to determining if a minimum flow bypass is required for the
selected pump to avoid pump overheating and mechanical damage.
NPSH as a measure to prevent liquid vaporization or called cavitation of pump. Net
Positive Suction Head (NPSH) is the total head at the suction flange of the pump less
the vapor pressure converted to fluid column height of the liquid. The design engineer
should always remember that pumps can pump only liquids, not vapors because when
a liquid vaporizes its volume increases greatly. For example: 1ft3 of water it will
vaporize to produce 1700ft3 of steam. This will cause the rise in temperature and
pressure drop in the fluid and pump will stop functioning because it has not sufficient
suction pressure present.
Pumping maximum temperatures is important in deciding pump construction style and
pump cooling and mechanical seal requirements. The minimum operating temperature
is to ensure that the material has adequate impact strength.
Specific gravity is parameter determines the pump head required to produce a desired
pressure increase. For pumps with limited head capability such as centrifugal pumps,
it affects pressure rise capability. Pump power requirements are also affected by
specific gravity.
Viscosity is important in the selection of pump type and has a significant effect on
centrifugal pump performance. Minimum values of viscosity are important in
determining rotary pump (positive displacement pump) performance, while maximum
viscosity is important in determining debits to centrifugal pump performance.
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
Page 10 of 51
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
Fluid solid content will affect the pump design. It affected the aspects of the design for
the flow characteristic, consideration design of erosion resistance, flow passage size,
impeller style, peripheral speed, design features to disintegrate large particles, and
shaft sealing design. This parameter has to be added in the data sheet for design.
Other process requirement such as flexibility for expansion should be consider as well.
This is important for future capacity expansion; it helps to minimize the cost of
expansion because to replace the pump will be a large sum of money. Working
capacity of pump should always be design for more than 20% extra design capacity.
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
Page 11 of 51
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
DEFINITION
Bearing Housing -The bearing housing encloses the bearings mounted on the shaft.
The bearings keep the shaft or rotor in correct alignment with the stationary parts
under the action of radial and transverse loads. The bearing house also includes an oil
reservoir for lubrication, constant level of oil, jacket for cooling by circulating cooling
water.
Capacity - Is the water handling capability of a pump commonly expressed as either
gallon per minute (gal/min) or cubic meter per minute (m3/min).
Cavitation - Is the result of vapor bubbles imploding. This occurs when the amount of
fluid flowing into the pump is restricted or blocked.
Discharge Port —Point where the discharge hose or pipe is connected to the pump.
Datum Elevation – It use as reference of the horizontal plane for which all the
elevations and head are measured. The pumps standards normally specify the datum
position relative to a pump part, eg. Centrifugal horizontal pump datum position is at
the impeller shaft centerline.
Dynamic Discharge Head- The static discharge head plus the friction in the
discharge line also referred to as Total Discharge Head.
Dynamic Suction Head - The static suction lift plus the friction in the suction line also
referred to as Total Suction Head.
Endurance limit – Is the stress below which the shaft will withstand an infinite number
of stress reversals without failure. Since one stress reversal occurs for each revolution
of the shaft, this means that ideally the shaft will never fail if the maximum bending
stress in the shaft is less than the endurance limit of the shaft material.
Friction Head-The head required to overcome the resistance to flow in the pipe and
fittings. It is dependent upon the size, condition and type of pipe, number and type of
pipe fittings, flow rate, and nature of the liquid.
Friction Loss - Refers to reductions in flow due to turbulence as water passes
through hoses, pipes, fittings and elbows.
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
Page 12 of 51
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
Impeller — A disk with multiple vanes. It is attached to the pump engine or motor and
is used to create the centrifugal force necessary for moving water through the pump
casing.
Mechanical Seal — A common wear part that forms a seal between the pump and
the engine or motor. Also prevents liquid from seeping into the engine or motor.
Net Positive Suction Head (NPSHa) - Is the total head at the suction flange of the
pump less the vapor pressure converted to fluid column height of the liquid
Net Positive Suction Head Required (NPSHr) - NPSH in meters (feet) determined
by Supplier testing, usually with water. NPSHR is measured at the suction flange and
corrected to the datum elevation. NPSHR is the minimum NPSH at rated capacity
required to prevent a head drop of more than 3% (first stage head in multistage
pumps) due to cavitation within pump.
Pressure Head - Pressure Head must be considered when a pumping system either
begins or terminates in a tank which is under some pressure other than atmospheric.
The pressure in such a tank must first be converted to feet of liquid. Denoted as hp,
pressure head refers to absolute pressure on the surface of the liquid reservoir
supplying the pump suction, converted to feet of head. If the system is open, hp equals
atmospheric pressure head.
Static Suction Head -Head resulting from elevation of the liquid relative to the pump
center line (datum). If the liquid level is above pump centerline (datum), hS is positive.
If the liquid level is below pump centerline (datum), hS is negative. Negative hS
condition is commonly denoted as a “suction lift” condition
Static Discharge Head - It is the vertical distance in feet between the pump centerline
and the point of free discharge or the surface of the liquid in the discharge tank.
Suction Port — Point where the suction hose or pipe is connected to the pump.
Vapor Pressure Head - Vapor pressure is the absolute pressure at which a liquid and
its vapor co-exist in equilibrium at a given temperature. The vapor pressure of liquid
can be obtained from vapor pressure tables. When the vapor pressure is converted to
head, it is referred to as vapor pressure head, hvp. The value of hvp of a liquid
increases with the rising temperature and in effect, opposes the pressure on the liquid
surface, the positive force that tends to cause liquid flow into the pump suction i.e. it
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
Page 13 of 51
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
reduces the suction pressure head. (Vapor pressure can be said as the external
pressure require to prevent fluid from evaporate become vapor).
Velocity Head - Refers to the energy of a liquid as a result of its motion at some
velocity ‘v’. It is the equivalent head in feet through which the water would have to fall
to acquire the same velocity, or in other words, the head necessary to accelerate the
water. The velocity head is usually insignificant and can be ignored in most high head
systems. However, it can be a large factor and must be considered in low head
systems.
Viscosity — is a mechanist of fluid resistance to flow of a liquid at a given
temperature. High viscosity liquids such as motor oil are more resistant to flow than
water.
Kinematics Viscosity (cSt) =
Absolute Viscosity (cP)
Specific Gravity
Volute — A stationary housing inside the pump housing in which the impeller rotates.
It is used to separate air and water.
Total Head - Pressure required in feet (meter) of head that the pump must produce.
The head at the discharge pump flange minus the head at suction flange.
NOMENCLATURE
C
D
g
Hc
Hd
Hs
Ht
ha
hf
hf(d)
Constant for pump geometry
Diameter of impeller, in
Acceleration due to gravity, 32.2 ft/s2 (9.81 m/s2)
Total head developed from centrifugal pump, ft
Discharge head, ft (m)
Suction head, ft (m)
Total head, ft (m)
Acceleration for the reciprocating pump only for calculate the head
losses due to pulsation in the flow, ft (m)
Head produce from pressure loss in pipe, fitting, and entrancement, ft
(m)
Head produce from pressure loss in pipe, fitting, and entrancement with
depend the pipe diameter and type of flow from discharge to destination,
ft (m)
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.
Page 14 of 51
KLM Technology
Group
Practical Engineering
Guidelines for Processing Plant
Solutions
hf(s)
hp
hp(d)
hp(s)
hst
hst(d)
hst(s)
hvp
K
L
n
P
Q
Q1
r
S
Tr
V
v
SECTION :
Pump Selection and Sizing
( ENGINEERING DESIGN GUIDELINE)
Rev: 03
May 2012
Head produce from pressure loss in pipe, fitting, and entrancement with
depend the pipe diameter and type of flow at suction section, ft (m)
Absolute pressure head on surface of liquid, ft (m)
Gauge pressure head on surface of liquid at destination, ft (m)
Gauge pressure head on surface of liquid at suction point, ft (m)
Head from the elevation between distance from suction surface to pump
centerline, ft (m)
Head from the elevation between distance from destination surface to
pump centerline, ft (m)
Head from the elevation between distance from suction surface to pump
centerline, ft (m)
Vapor pressure of the liquid converted, ft (m)
A factor representing the relative compressibility of the liquid
Length of the suction line from the nearest upstream vessel (or suction
stabilizer) to the pump, (ft or m)
Impeller RPM (Revolutions per minute)
Pressure in system, psi (kg/cm2)
Capacity, gal/min (m3/min)
Capacity, ( m3/s)
Radius of shaft (rad)
Specific gravity
Shaft Torque (Nm)
Average velocity in the suction line, ft/s (m/s)
Velocity of periphery of impeller (tip speed), ft/s (m/s)
Greek letters
ηp
Pump efficiency, %
ρ
π
ω
Fluid density, Ib/ft3 (kg/m3)
pi ( 3.142)
Shaft angular velocity (rad/s)
These design guideline are believed to be as accurate as possible, but are very general and not for specific design
cases. They were designed for engineers to do preliminary designs and process specification sheets. The final
design must always be guaranteed for the service selected by the manufacturing vendor, but these guidelines will
greatly reduce the amount of up front engineering hours that are required to develop the final design. The guidelines
are a training tool for young engineers or a resource for engineers with experience.
This document is entrusted to the recipient personally, but the copyright remains with us. It must not be copied,
reproduced or in any way communicated or made accessible to third parties without our written consent.